diff -u -r agg-2.5/include/agg_renderer_outline_aa.h agg-2.5-const/include/agg_renderer_outline_aa.h
--- agg-2.5/include/agg_renderer_outline_aa.h	2006-10-09 06:07:08.000000000 +0200
+++ agg-2.5-const/include/agg_renderer_outline_aa.h	2018-06-16 23:09:16.500057814 +0200
@@ -1375,7 +1375,7 @@
         //---------------------------------------------------------------------
         void profile(const line_profile_aa& prof) { m_profile = &prof; }
         const line_profile_aa& profile() const { return *m_profile; }
-        line_profile_aa& profile() { return *m_profile; }
+        line_profile_aa& profile() { return *const_cast<line_profile_aa*>(m_profile); }
 
         //---------------------------------------------------------------------
         int subpixel_width() const { return m_profile->subpixel_width(); }
